The total number of integer pairs (x, y) satisfying the equation x + y = xy is

If a, b and c are the sides of a triangle and a⁴ + b⁴ + 2a²b² = c⁴, then the triangle is

Which of the following is true?

If 9c + 2d = 11 and z – 3d = 5, then what is the value of g?

Which family has the lowest average savings?

If a sum of money at certain rate of interest doubles in 5 years and at a different rate of interest becomes 3 times in 12 years, the better rate of interest is

H.C.F. of two polynomials is a + 5 and their L.C.M. is (a + 5) (a + 4) (a – 1). If one of the polynomial is a²+ 4a – 5,then the other polynomial is

The sum of X and Y's age is 105. When X was Y's age, she was 1.5 times Y's age then what are their present ages?

If x = 1 – q and y = 2q + 1, then for what value of q, x is  equal to y?

If k – 7 = 7 (1 – k), then what is the value of k?